Project : Genetics
Due: November 22nd, 2000
Let us assume Auto-somal inheritance,(i.e. an individual inherits one gene from each of its parent's pairs of genes to form its own particular pair). Suppose a farmer has a large population of plants consisting of
some distribution of all three possible genotypes AA,Aa, and aa.
|
Genotype of parents |
|
AA-AA |
AA-Aa |
AA-aa |
Aa-Aa |
Aa-aa |
aa-aa |
Genotype |
AA |
1 |
0.5 |
0 |
0.25 |
0 |
0 |
of |
Aa |
0 |
0.5 |
1 |
0.5 |
0.5 |
0 |
offspring |
aa |
0 |
0 |
0 |
0.25 |
0.5 |
1 |
The probabilities of the possible genotypes of the off-spring for all
possible combinations of the genotypes of the parents be given by the
above table. Note that all the table is saying is that any of each parent's two genes is equally likely to be inherited by the offspring.
Let
denote the fractions of the initial population of
genotypes AA,Aa,aa, respectively.
- She desires to undertake a breeding program in which each plant in
the population is always fertilized with a plant of genotype AA.
- Derive an expression for the distribution of the three possible
genotypes in the population in the first generations in terms of the
fractions present in the initial population.
- Derive an expression for the distribution of the three possible
genotypes in the population after
number of generations in terms of the fractions present in the
generation.
- Using the Singular Value Decomposition (or otherwise) derive an expression
for the distribution of the three possible genotypes in the population
after
number of generations in terms of the fractions present in
terms of the initial population.
- Find the limiting genotype distribution as
.
- A friend of her's in another farm, modifies the fertilization
program. He desires to undertake a breeding program in which each
plant in the population is fertilized with a plant of its own
genotype.
- Use the steps outlined in question (1) to derive an
expression for the distribution of the three possible genotypes in the
population after
number of generations.
- Find the limiting genotype distribution as
.